"Pled" is the past tense of "plead". "Plead" usually means to beg. Thus "pled" would mean "begged". "Plead" can also mean "to put forth a plea". Thus in a legal context, a defendant will "plead" a plea of guilty or not guilty.
"Pled" is an alternative past tense (the other is "pleaded") of "to plead", which means "to argue from a subservient position on behalf of oneself or another person, group, or cause.
